<meta charset="utf-8">
(#) Marks usage of the requireNotNull method without lazy messages

!!! WARNING: Marks usage of the requireNotNull method without lazy messages
   This is a warning.

Id
:   `KotlinRequireNotNullUseMessage`
Summary
:   Marks usage of the requireNotNull method without lazy messages
Severity
:   Warning
Category
:   Correctness
Platform
:   Any
Vendor
:   vanniktech/lint-rules/
Feedback
:   https://github.com/vanniktech/lint-rules/issues
Min
:   Lint 8.0 and 8.1
Compiled
:   Lint 8.0 and 8.1
Artifact
:   [com.vanniktech:lint-rules-kotlin](com_vanniktech_lint-rules-kotlin.md.html)
Since
:   0.22.0
Affects
:   Kotlin and Java files
Editing
:   This check runs on the fly in the IDE editor
Implementation
:   [Source Code](https://github.com/vanniktech/lint-rules/tree/master/lint-rules-kotlin-lint/src/main/kotlin/com/vanniktech/lintrules/kotlin/KotlinRequireNotNullUseMessageDetector.kt)
Tests
:   [Source Code](https://github.com/vanniktech/lint-rules/tree/master/lint-rules-kotlin-lint/src/test/kotlin/com/vanniktech/lintrules/rxjava2/KotlinRequireNotNullUseMessageDetectorTest.kt)

The default generated message from requireNotNull often lacks context,
hence it's best to provide a custom message.

(##) Example

Here is an example of lint warnings produced by this check:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text
src/test.kt:2:Warning: Provide a message
[KotlinRequireNotNullUseMessage]
  requireNotNull(value)
  --------------
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Here is the source file referenced above:

`src/test.kt`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~kotlin linenumbers
fun test(value: Int?) {
  requireNotNull(value)
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You can also visit the
[source code](https://github.com/vanniktech/lint-rules/tree/master/lint-rules-kotlin-lint/src/test/kotlin/com/vanniktech/lintrules/rxjava2/KotlinRequireNotNullUseMessageDetectorTest.kt)
for the unit tests for this check to see additional scenarios.

The above example was automatically extracted from the first unit test
found for this lint check, `KotlinRequireNotNullUseMessageDetector.requireNotNull`.
To report a problem with this extracted sample, visit
https://github.com/vanniktech/lint-rules/issues.

(##) Including

!!!
   This is not a built-in check. To include it, add the below dependency
   to your project. This lint check is included in the lint documentation,
   but the Android team may or may not agree with its recommendations.

```
// build.gradle.kts
lintChecks("com.vanniktech:lint-rules-kotlin:0.25.0")

// build.gradle
lintChecks 'com.vanniktech:lint-rules-kotlin:0.25.0'

// build.gradle.kts with version catalogs:
lintChecks(libs.lint.rules.kotlin)

# libs.versions.toml
[versions]
lint-rules-kotlin = "0.25.0"
[libraries]
# For clarity and text wrapping purposes the following declaration is
# shown split up across lines, but in TOML it needs to be on a single
# line (see https://github.com/toml-lang/toml/issues/516) so adjust
# when pasting into libs.versions.toml:
lint-rules-kotlin = {
    module = "com.vanniktech:lint-rules-kotlin",
    version.ref = "lint-rules-kotlin"
}
```

0.25.0 is the version this documentation was generated from;
there may be newer versions available.

[Additional details about com.vanniktech:lint-rules-kotlin](com_vanniktech_lint-rules-kotlin.md.html).
(##) Suppressing

You can suppress false positives using one of the following mechanisms:

* Using a suppression annotation like this on the enclosing
  element:

  ```kt
  // Kotlin
  @Suppress("KotlinRequireNotNullUseMessage")
  fun method() {
     requireNotNull(...)
  }
  ```

  or

  ```java
  // Java
  @SuppressWarnings("KotlinRequireNotNullUseMessage")
  void method() {
     requireNotNull(...);
  }
  ```

* Using a suppression comment like this on the line above:

  ```kt
  //noinspection KotlinRequireNotNullUseMessage
  problematicStatement()
  ```

* Using a special `lint.xml` file in the source tree which turns off
  the check in that folder and any sub folder. A simple file might look
  like this:
  ```xml
  &lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;lint&gt;
      &lt;issue id="KotlinRequireNotNullUseMessage" severity="ignore" /&gt;
  &lt;/lint&gt;
  ```
  Instead of `ignore` you can also change the severity here, for
  example from `error` to `warning`. You can find additional
  documentation on how to filter issues by path, regular expression and
  so on
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html).

* In Gradle projects, using the DSL syntax to configure lint. For
  example, you can use something like
  ```gradle
  lintOptions {
      disable 'KotlinRequireNotNullUseMessage'
  }
  ```
  In Android projects this should be nested inside an `android { }`
  block.

* For manual invocations of `lint`, using the `--ignore` flag:
  ```
  $ lint --ignore KotlinRequireNotNullUseMessage ...`
  ```

* Last, but not least, using baselines, as discussed
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).

<!-- Markdeep: --><style class="fallback">body{visibility:hidden;white-space:pre;font-family:monospace}</style><script src="markdeep.min.js" charset="utf-8"></script><script src="https://morgan3d.github.io/markdeep/latest/markdeep.min.js" charset="utf-8"></script><script>window.alreadyProcessedMarkdeep||(document.body.style.visibility="visible")</script>